This invention relates generally to a direct lighting/illuminating system for CCD cameras, and in particular, to direct lighting/illuminating systems for miniature CCD cameras used with direct contact microscope imagery.
In the past a CCD camera was attached to the eye piece of a microscope to make analytical observations of an object. The illuminating method generally used a lamp, a metallic reflector for the microscope and a fiber optic direct angular illuminator or other similar lighting source.
There was no problem in the past using this system since CCD cameras then, were large and bulky. Recently developed CCD cameras are less than 1 cm in diameter which are highly miniaturized and with the attachment of the microscope's objective lens to the CCD camera further miniaturization has become possible. In the mean time a problem has developed concerning the adequacy of illuminating a subject object under a miniaturized CCD camera. It has been found that the traditional light source will not illuminate and disperse light evenly on an object surface when the new CCD camera is used.
The inventor is aware of several U.S. patents of interest, the following list shows the recent state of the art of microscope illuminating systems: U.S. Pat. No. 4,351,584, issued to Chandesais; U.S. Pat. No. 4,464,705, issued to Horowitz: U.S. Pat. No. 4,637,691, issued to Uehara et al: U.S. Pat. No. 4,650,279, issued to Magee: U.S. Pat. No. 4,683,524, issued to Ohta; and U.S. Pat. No. 4,725,727, issued to Harder et al.
Referring to the Chandesais patent, U.S. Pat. No. 4,351,584, ring lighting for microscopes is disclosed. A light source remote from the object being examined illuminates the object via a fiber optic guide extending to an annular endpiece and a reflector. Light passing through the fiber optic guide is reflected off the ring reflector and directed on the object.
U.S. Pat. No. 4,725,727, issued to Harder et al is directed to a waveguide for an optical near-field microscope. Transparent optical bodies are coated with an opaque material and the apex of the optical bodies are removed so to expose the transparent body through a first aperture and to expose the transparent layer through a second aperture. Light enters the transparent body at its remote end and exits through the first aperture to illuminate an object. Reflected light from the object enters the transparent layer through the second aperture and is guided to a light detector for further processing.
The Harder et al patent is a patent the inventor is aware of which addresses an illuminating system which uses fiber optics, FIGS. 6 and 7, to illuminate an object using an optical near-field microscope. Near-field optical microscopes are used to examine objects that are almost invisible to the eye, such as viruses, bacteria and electronic circuits. The present problem is how to improve the resolving power of these microscopes. There are two pending U.S. Patent applications cited in Harder et al on the subject of near-field microscopes with apertures smaller than one wavelength to control resolution. The present invention uses a direct contact microscope which does not require adjustment to achieve good resolution; and the illumination system evenly disperses light for use with a miniature CCD camera which is suitable for color dispersion and other analytical purposes.